Would you like if all people became atheists?

[Simsim]

However, during my time as a Christian, I heard copious amounts of comments in passing that suggested that individual was possibly mentally unstable. If they weren't bound by eternal threats of punishment, then they would be harming society.

An example of this is one of my good friends at the time who, in passing, said that atheists should be having as much sex as possible since there's no objective to life. This means that if he were to deconvert right now, there's no mental filter in place to stop him from potentially getting sex in ways that violate other people's rights, as quite clearly, he projected his belief that he would want as much sex as possible.

It seems to me that unfortunately, religion is necessary for a select few who are on the border of becoming a real danger to society, and thus I do not wish for them to be atheists for their sake and mine.

Religious people say that always, if there are no punishments so why being good or abstaining from evil?
But if you ask them: How do you know that this is "evil"?

The knowledge of "good" and "evil" is, somehow, innate in the human race but not religions. When disposing of religion even deep religious people behave normally, if not better, without need to religious roles. That is, What makes them know the difference between good and evil without religion makes them also act according to their knowledge of good and evil.